Magnetic blowout system for high-voltage contactors



Dec. 16, 1952 F. Y. GREPE 2,622,173

MAGNETIC BLOWOUT SYSTEM FOR HIGH-VOLTAGE CONTACTORS v INVENTOR. FfiiflfR/C/f y. GAM 5,

ATTORNEY F. Y. GREPE Dec. 16, 1952 MAGNETIC BLOWOUT SYSTEM FOR HIGH-VOLTAGE CONTACTORS Filed March 19, 1947 4 Sheets-Sheet 2 INVENTOR.

mvpfzr/c/r K 6/? Dec. 16, 1952 F. Y. GREPE 2,622,173

MAGNETIC BLOWOUT SYSTEM FOR HIGH-VOLTAGE CONTACTORS Filed March 19, 1947 4 Sheets-Sheet :5

' INVENTOR,

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7 1 l L a I A fro/7N5) Dec. 16, 1952 H F. Y. GREPE 3 V MAGNETIC BLOWOUT SYSTEM FOR HIGH-VOLTAGE CONTACTORS Filed March 19, 1947' 4 Sheets-Sheet 4 INVENTOR. F/PffifR/CA K 685/ 5,

6 Arraizwzr 7 Patented Dec. 16, 1952 MAGNETIC BLOWOUT SYSTEM FOR HIGH- VOLTAGE CONTACTORS Frederick Grepe, Toronto, Ontario, Canada, assignor to Canadian Controllers, Limited, Toronto, Ontario, Canada Application March 19, 1947, Serial No. 735,635 In Canada March 3, 1947 My invention relates broadly to high voltage contactors and more particularly .toan improved structure of high voltage contactor assembly.

One of the objects of my invention is to provide a construction of improved high voltage contactor system in which an efiective magnetic arc blowout is associated in compact .relation to. an electromagnetically controlled circuit .opening and closing contact system. 1 i

Another object of my inventionnis to provide an arrangement of arc runners capacitatively coupled to the contacts of a switching system whereby the arc may be rapidly transferred from the contactor make and break system to the arc runners and efiectively dissipated.

Still another object ofmy invention is to provide an arrangement of magnetic system in association with are runners which are capacitatively coupled with the main contacts of a switching system and arranged adjacent an arc dissipating structure in such manner that arcs which develop upon the opening of the main contacts are rapidly displaced from the main contacts onto the arc runners and quenched in the arc dissipating structure.

Still another object of my invention is to provide an improved and practicalf'form of arc quenching structure which may' be'readily supported adjacent arc'runners which arecapacitatively related to the main contactsof a switching system, the arc quenching structure being readily removable and'replaceable-with respect to the arc runners for convenient maintenance and replacement fromtime to time.

Still another object'of my invention is to provide an arrangement of magnetic blowout system for contactors in which a multiple winding magnetic blowout circuit is associated with the main contacts, runners and line supply circuit to the load for insuringrapid displacement of a formed are from the main contacts to'arc runners for rapid dissipation in an associated arc quenching system.

Other and further objects of my invention reside in an improved construction of magnetic blowout system for highvoltage contactors which is capable of manufacture and production inexpensively on a quantity production basis as set forth more fully in the specification hereinafter following by reference to the accompanying drawings in which:

Figure l isa fro-nt elevational view showing the polyphase contactor assembly embodying my invention and operated by anelectromagnetic actuator; Fig.2 is a side elevational'view of the 11 Claims. (01. 200--147 c g 2' magnetic blowout system for high voltage contactors of my invention; Fig. 3 is a vertical sec- 'tional View taken substantially on line 3 3 of Fig. 1; Fig. i is a transverse sectional view taken substantially on line, 4-4 of Fig. 3; Fig. 5 is a transverse sectional view taken substantially on line 55 of Fig. 3; Fig. 6 is a perspective view of one of the magnetic pole pieces of the magnetic blowout system employed in the apparatus of my invention; and Fig.- 7 is a schematic View illustrating the capacitative relation of the arc runners and the contacts and the electrical connection oi the magnetic blowout exciting windings.

which is replaceably and renewably supported on conductive standard} bybolt member la. The conductive standard 2 is mounted upon insulated panel support 25 which supports the magnetic blowout system, the contact system and the arc quenching system. The stationary contact I is directly aligned with the movable contact 3 which is renewably and replaceably supported by means of bolt member 3a in arm 4 operated by the switch actuator as will be hereinafter described. The stationary contact I is capacitatively associated with the rear arc runner contact 6 which is renewably and replaceably suppOrted in the rear arc runner bracket 5 supportedon the insulated panel structure 25. The rear are runner bracket structure 5 is recessed at Bate receive the renewable and replaceable rear arc runner 6 which is secured thereto by means of bolt member 6a. The upper end of the rear arc runner bracket is provided with a hook-shaped bracket extension 5b adapted to receive and support the removable and replaceable arc quenching box represented generally at 26.

The movable contact -3 has associated therewith the movable front are runner I! in theform of an angular strip member which is permanently secured in position by bolt member 3a on arm 4 and capacitatively related to the front are runner IS. The capacitative relation of the movable front are runner I1 and the front are runner I5 is maintained throughout the movement of operating'arm 4' in establishing and breaking electrical connection between movable contact 3 and stationary contact I. The front arcrunner I6 is shaped as represented at Ilia to provide an obtuse angle recess therein to serve as a rear bracket for supporting the renewable replaceable arc quenching box 26.

The are quenching box 28 in renewable and replaceable with respect to the hook-shaped portion bracket of the rear arc runner bracket 5 and is supported with respect to the rear of panel 25 by means of the hook-shaped portion 5?) of bracket 5 and the transversely extending bolt member 29, the ends of which fit into the recesses 22a in brackets 22 which are supported with respect to the rear of the panel structure 25. The are quenching box 26 comprises substantially parallel extending plate members 8 and 9 of insulation material which are spaced at their rear edges by the strip of insulation material 1 and which are spaced at their front edges by the strip of insulation material It. The insulated plates 8 and 9 are spaced at their lower front edges by means of front arc runner l3 secured between the plates 8 and 9 by bolt members 16b. Plates 8 and 9 of insulation material form a closure for the central plate I l of insulation material which supports the spaced arc dis charge pins 12. The insulated plate H is supported by means of transversely extending bolt members 21 which pass through the plate members 8 and 9 and through the central plate H and through the gas coolers l4 and I5 and are fastened exteriorly of the plates 8 and 9 by nuts 21a.

The gas coolers l4 and are formed from asbestos board or transite plates which extend horizontally across the interior of the arc quenching unit. These gas coolers are formed from are resisting material and are disposed in the path of what amounts to an open stack formed by the space between the asbestos liners 53 and 52 which line the interior of plates 9 and 9 which is open at the base and open at the top for the free passage of air currents around the contacts I and 3 and around the contact 5, around the rear arc runner structure 5 and front are runner H3 and movable front arc runner ll and through the arc discharge pins l2 and the gas coolers l4 and 15 for discharge through the open space at the top of plates 8 and 9. The gas coolers l4 and I5 and the liners 53 and 52 are approximately in thickness and occupy a minimum of space. The plates 8 and 9 are fastened at their front edges by bolt members 28 and at their rear edges by bolt member 29 and bolt member 29 to form the enclosed arc quenching unit. The rear closure strip 1 which serves to space plate members 8 and 9 and through which bolt member and bolt member 29 transversely extend is shaped at the lower end thereof as represented at la to effect detachable engagement with the hook-like projection 5b: of the rear arc runner structure 5 thus coacting with the engagement of the ends of bolt member 29 in slot 22a of brackets 22 in detachably mounting the arc quenching unit.

The magnetic blowout system associated with the contacts I and .3 consists of a pair of magnetic plate members l8 and 19 which project through slots 25a and 25b in insulated panel 25 and are supported with respect thereto by means of angle members 2| which are mounted by means of bolt members 21a on insulated panel 25. The magnetic plate members I8 and I9 are formed from magnetic laminations which are secured together and are provided with pole faces 18a and |9a which are shaped in a very special manner. The pole faces 18a and 19a are elongated in shape to effect a distribution of magnetic lines of force immediately within the area of the contact 5, rear arc runner 5 and front are runner I5. The magnetic lines of force tend to shift the are which is transferred along mow able front are runner i! at the time of break of the connection between contact 3 and contact into the arc quenching system comprising pins 2. The ends of the magnetic plates [3 and I9 which project forwardly of the insulation panel 25 are interconnected by magnetic core structure 39 radially slotted at 35a to eliminate eddy current losses and fastened by bolt member 3| between the magnetic plates [8 and [9. At the position of support of the core structure 39, I provide vertically extending slots 18b and I91) in the magnetic plates l3 and [9 for eliminating eddy current losses. The magnetic core 39 supports an insulated spool member 32 which carries a pair of series connected windings 33 and 35.

The multiple winding on spool 32 consists of two series connected windings 33 and 3:1, the two windings being connected intermediate the terminals thereof at 35 and connected to terminal 39 which connects to the stationary contact I. The first winding 34 on the blowout magnet is of a heavy gauge wire of a few turns to be consistent with the load which the breaker will carry and to keep normal temperatures. Winding 34 has a relatively small number of ampere turns. The second winding 33 on the blowout system consists of as many turns as desired and of a smaller size wire to create a strong field for the moment of interruption. Winding 33 has a relatively large number of ampere turns. As the second winding is not in series with the load itself a light wire can be used and a proportionally larger number of turns in keeping with space and cost. The blowout windings 33 and 34 are connected in a manner that the heavy winding 34 of a few turns remains in series with the load when breaker is in the closed position and the second winding 33, through the medium of the are as a connecting link, is energized for the period when the breaker opens so that windings 33 and 34 of the blowout system are in series with each other during the period when the breaker opens, and so create a strong field when it is most needed.

The magnetic actuator for the contactor may be constructed in a variety of different ways. I have illustrated for purposes of explaining my invention an arrangement of actuating shaft 39 which is journalled in bearings supported in brackets 49 extending from the rear of panel 25. The shaft 39 has clamped thereto the angularly shiftable member 4! which resiliently supports the operating arm 4 carrying the movable contact 3. The resilient cushioning means between arm 4 and operating member Al is represented generally at 42. The magnetic actuator for the shaft 39 is represented at 43 including the operating magnet 44 and the armature 45. Energization of the operating magnet 44 attracts armature 45 and angularly rocks shaft 39 for shifting the movable contact 3 into electrical connection with contact I.

Electrical connection is taken from movable contact 3 and from front are runner 16 through flexible leads 4% and M, respectively, the leads terminating at terminal connection 48 supported on connector plate 49 carried by spacing insulator 59 extending from the rear of panel 25. Electrical connection is made to movable contact 3 and front are runner [5 through lug 5| secured to connector plate 49.

As contact 3 moves away from contact I an arc is formed. The action of the flux produced by the fewturn coil 34 is to lift the arc fromcontact l' to contact 6 and from contact 3.along runner II to runner Hi. When the arc is transferred from contact I to contact 6 the many turn coil 33 on the blowout coil is connected in series with the few turn coil 34 so producing anintense field which moves the are along runners 5 and I6 very rapidly and also up and into the pins [2 where the arc dissipated. The are is thus extinguished rapidly and does not build up into an intens and destructive discharge.

The magnetic pole pieces I81; and {9a, are elongated in structure and extend approximately parallel with the axis of the are discharge between the arc runners5 and i6. The magnetic faces I81; and [9a are elevated slightly above the general axis of the surface of the arc'runners 5 and I'Bsufficient to move the arc from'the arc runners into the arc dissipating systeni constituted by pins l2 for extinguishing the arc.

The several box-like closure members which house the plates ll carrying the arc discharge pins l2 are readily renewable and replaceable over the contacts I and 3. The contacts 'I and 3, contact 6, movable front arc runner I"! and front are runner I5 are all readily renewable and replaceable. Thus maintenance of the arc quenching system may be very readily accomplished and repairs and replacements made inexpensively and with minimum shutdown time of the eontactor system.

I have found the structure of my invention as set forth herein very practical for manufacture and efficient in operation. I realize however that changes may be made in the details of the structure of the apparatus and 'I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim as newand desire to secure by Letters Patent of the United States is as follows:

' 1. In a high-voltage circuit breaker construction, a rearward main support, stationary and movable make-and-break main contacts mounted on the support, forwardly and rearwardly aligned, a stationary arc runner mounted directly on the support above the stationary main contact and independently of the stationary contact, a box-like arc chute detachably mounted on the support and readily removable therefrom, and comprising opposite spaced side walls depending below and at opposite sides of the main contacts and stationary arc runner, an arc runner mounted upon and between the chute side walls and above the movable contact and removable in unison with the arc chute, an arc cooling structure secured to and within the arc chute walls substantially filling the arc chute above the runners, a'blowout magnet comprising pole pieces extending forwardly from the main support along the opposite side walls and outside the arc chute and supported stationarily by the main support independently of the removable arc chute, and embracing therebetween the contacts and are runners.

2. In a high-voltage circuit breaker construction, a rearward main support, stationary and movable make-and-break main contacts mounted on: the support, forwardly and rearwardly aligned, a stationary arc runner mountedon the support above the stationary main contact, a I box-like arc chute detachably mounted on the 'fsuppo'rt and readily removable therefrom, and

comprising opposite spaced sidewalls depending below and at opposite sides of the main contacts and stationary arc runner, an arc runner mounted upon and between the chute side wallsand above the -movable contact and removable in unison with the arc chute, an arc cooling structure secured to and within the arc chute walls substantially filling the are chute above the runners, a blowout magnet comprising pole pieces extending forwardly from the main support along the opposite side walls and outside the arc chute and supported stationarily on the main support independently of the removable arc chute, and embracing therebetween the contacts and are runners, the arc runners having arcing portions generally aligned at a rearward, upward, inclination, and the pole pieces of the magnet having mutually confronting elongated inwardly extending pole portions substantially opposite to and parallel with the aligned arcing portions of the runners.

3. In a high-voltage circuit breaker, a pair of main contacts, are runners associated respectively with and above the main contacts and separated therefrom respectively by air gaps, an-arc blowout magnet comprising a core and a winding on the core and magnet pole pieces at opposite sides of the contacts and runners receiving flux from the core, arranged to cause the are drawn initially between the main contacts to rise and leave both main contacts and transfer completely from the main contacts to the arc runners when the winding is energized and the main contacts open; the winding being in two parts, one part being connected to be in series with the circuit to be broken and with the main contacts and with the arc therebetween, the two parts bein connected to be in series with each other and with the main circuit to be broken and with the two are runners and the arc therebetween when the arc has completely transferred to the runners.

4. In a high-voltage circuit breaker, a pair of main contacts, are runners associated respectively with and above the main contacts and separated therefrom respectively by air gaps, an arc blowout magnet comprising a core and a winding on the core, and magnet pole pieces at opposite sides of the contacts and runners receiving flux from the core, arranged to cause the are drawn initially between the main contacts to rise and leave both main contacts and transfercompletely from the main contacts to the are runners when the winding is energized and the main contactsopen; the winding being in two parts, circuit connections causing one part of the winding to be energized alone by the main circuit current while the main contacts are closed and while the arc bridges them after they open, andcausing both parts to be energized in series by the main circuit current when the arc has transferredto the arc runners, and current flow between the main contacts has ceased.

5. In connection with a circuit breaker of the type comprising an arc chute having thereinpmain contacts, are runners above the main, contacts respectively, and transverse arc cooling structure above the arc runners; the method of breaking an are drawn initially between the main contacts, which includes producing a magnetic field transversely of the are which has an upper portion stronger than the lower portion subjecting the arc to the lower magnetic field portion to cause the arc'to rise and form on the arc runners and become elongated. thereon, and subjecting the rising elongated are on the arc: .runnersioo a stronger upper magnetic field portion to force it upwardly into the arc cooling structure.

6. The method of rupturing an arc drawn between circuit breaker contacts upon opening of the contacts to a predetermined distance, which includes: producing a magnetic field transversely of the are which has an upper portion stronger than the lower portion subjecting the arc to the lower magnetic field portion to cause it to rise; causing the feet of the arc to separate to a greater distance apart than the distance between the contacts to elongate the arc; abruptly still further increasing the strength of the upper portion of the magnetic field and subjecting the elongated arc thereto to cause it to be forced upwardly; and subtracting heat from the upwardly forced elongated arc and splitting the arc to extinguish the arc.

7. A magnetic blowout system for high voltage contactors comprising a pair of circuit opening and closing contacts one of which has a generally horizontal path of movement into and out of contacting relation with the other, an arc dissipating structural system arranged above said contacts with its lower termination above the contacts, a magnetic system including a pair of elongated pole pieces extending longitudinally along opposite sides of said contacts, a pair of rib-like magnetic pole portions on the respective magnetic pole pieces, extending longitudinally thereof and mutually confronting each other, said pole portions being disposed above the said contacts and generally parallel to the horizontal path of movement thereof adjacent to the lower termination of said are dissipating system for magnetically forcing an arc, established between and rising from said contacts upwardly into said arc dissipating system,

8. A magnetic blowout system for high voltage contactors comprising a pair of circuit opening and closing contacts one of which has a generally horizontal path of movement into and out of contacting relation with the other, an arc dissipating structural system arranged above said contacts with its lower termination above the contacts, a magnetic system including a pair of pole pieces extending along opposite sides of said contacts, a magnetic pole portion on each of said magnetic pole pieces extending toward each other, said pole portions being elongated and disposed above the said contacts and extending generally parallel to the path of movement of said one of said contacts and adjacent to the lower termination of said arc dissipating system for magnetically forcing an arc, established between and rising from said contacts upwardly into said arc dissipating system.

9. A magnetic blowout system for high voltage contactors comprising a pair of circuit opening and closing contacts one of which has a generally horizontal path of movement into and out of contacting relation with the other, a pair of arc runners, each disposed above one of the said contacts, an arc dissipating structural system arranged above said contacts with its lower termination above the contacts and adjacent to the runners, a magnetic system including a pair of magnetic pole pieces extending along opposite sides of said contacts for magnetically causing an are drawn on the contacts to rise and transfer to the arc runners, a magnetic pole portion on each of said magnetic pole pieces extending toward each other, said magnetic pole portions being elongated and disposed above the said contacts and extending generally parallel to the path of movement of said one of said contacts and ad jacent to said runners and to the lower termination of said are dissipating system for magnetically forcing the are on the runners upwardly into the arc dissipating system.

10. A magnetic blowout system for high voltage contactors comprising a generally vertical arc chute, a pair of circuit opening and closing contacts in a lower part of the arc chute, one movable relative to the other in a substantially horizontal path, an arc dissipating system in an upper part of the arc chute, and above the contacts, a magnetic system including a pair of elongated pole pieces on the outside of the arc chute extending longitudinally along opposite sides of said contacts, a pair of rib-like magnetic pole portions on the respective magnetic pole pieces extending longitudinally thereof and mutually confronting each other, said pole portions being elongated and being positioned opposite the lower part of the arc dissipating system, and above the contacts generally parallel to the horizontal path of movement thereof, an arc runner connected with the movable one of said contacts, separate stationary arc runners associated respectively with the contacts and above them and below the arc dissipating system.

11. A magnetic blowout system for high voltage contaotors comprising a pair of circuit opening and closing contacts, an arc runner electrically associated with each of said contacts and above it, an arc dissipating system above said arc runners, a magnetic blowout system including a pair of magnetic pole pieces extending along opposite sides of said contacts and said are runners and the lower part of said are dissipating system, electric circuit means connected to the contacts and are runners and comprising winding means for magnetically energizing the pole pieces, the pole pieces formed to subject an are drawn on the contacts to distributed flux to move the arc upwardly and effect its transfer to the arc runners and formed to subject the transferred arc to concentrated flux to force it into the arc dissipating system.

FREDERICK Y. GREPE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,364,389 Lindquist et a1 Jan. 4, 1921 1,533,251 Johnston Apr. 14, 1925 1,742,565 Traver Jan. 7, 1930 2,242,905 Dickinson et al. May 20, 1941 2,249,499 Seaman July 15, 1941 2,255,886 Hudson Sept. 16, 1941 2,276,859 Nau Mar. 17, 1942 2,293,487 Bartlett Aug. 18, 1942 2,381,637 Bohn Aug. 7, 1945 2,417,134 Scott, Jr Mar. 11, 1947 2,436,189 Boehne Feb. 17, 1948 2,446,027 Scott, Jr July 27, 1948 FOREIGN PATENTS Number Country Date 250,450 Italy Oct. 7, 1926 335,917 Germany Apr. 16, 1921 416,461 Germany July 18, 1925 696,410 Germany Sept. 20, 1940 702,431 Germany Feb. 7, 1941 837,964 France Nov. 28, 1938 860,510 France Sept. 30,, 1940 

